JPH08313975A - Finder driving mechanism - Google Patents

Abstract

PURPOSE: To provide a finder driving mechanism capable of miniaturizing a camera by providing a mechanism for the forward and backward movement driving of a finder optical system, linked with the forward and backward movements and rotation of a lens frame. CONSTITUTION: The finder driving mechanism is provided with a photographic lens frame 1 being capable of moving to extended and retracted positions and freely rotatable around an optical axis, a finder provided with movable lenses 8 and 9 moving in an optical direction and a long gear 2 and a cam shaft 7 capable of transmitting the rotation of the lens frame 1 to the movable lenses 8 and 9 of the finder, regardless of the forward and backward movement actuation of the lens frame 1. The rotational force of the lens frame 1 can be transmitted to the movable lenses 8 and 9 by the long gear 2 and the cam shaft 7, to attain the variable power driving of the movable lenses 8 and 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a finder drive mechanism,
More specifically, the present invention relates to a drive mechanism for a finder movable lens that interlocks with a taking lens.

[0002]

2. Description of the Related Art As a general mechanism used in a compact camera as a drive mechanism of a variable power finder of a conventional camera, a movable lens of a finder optical system is provided on a rotary ring for driving a taking lens barrel. In many cases, a grooved cam is used to move forward and backward in conjunction with the lens barrel, but the shooting lens barrel can be extended from the retracted position in the stored state to the shooting position that allows shooting. Is. However, the rotary ring has a structure in which it is not driven back and forth when it is extended.

[0003]

In the above-described camera having a built-in drive mechanism for the movable lens of the viewfinder, since the rotary ring does not perform forward / backward drive when the lens frame is extended from the retracted position to the photographing position, The depth dimension of the camera becomes large when the lens barrel is collapsed, which is an obstacle to downsizing of a compact camera. Therefore, a lens barrel in which the rotary ring is similarly extended when the lens frame is extended from the retracted position to the photographing position is conceivable. However, in that case, it is necessary to drive the viewfinder optical system forward and backward by the cam of the rotating ring that moves forward and backward, and such a configuration cannot be realized by the conventional viewfinder drive mechanism.

The present invention has been made to solve the above-mentioned problems, and in a finder drive mechanism incorporated in a camera having a lens barrel that can be retracted, it is interlocked with the advance / retreat and rotation of the lens barrel. It is an object of the present invention to realize a mechanism for driving the finder optical system to move forward and backward, and further to provide a finder driving mechanism that enables downsizing of the camera.

[0005]

Means and Actions for Solving the Problems First of the Invention
The finder drive mechanism of (1) is a photographic lens frame that can be moved back and forth between a retracted position and a retracted position and is rotatable around the optical axis, a finder having a movable lens that moves in the optical axis direction, and the photographic lens mirror described above. A drive transmission means capable of transmitting the rotation of the photographing lens to the movable lens of the finder regardless of the forward / backward movement of the frame. In the finder drive mechanism, the rotational force of the photographing lens is transmitted to the movable lens of the finder by the drive transmission means, and the movable lens is driven.

A second finder drive mechanism according to the present invention comprises a taking lens barrel which can be moved in the optical axis direction and rotatable about the optical axis, a finder having a movable lens which can be moved in the optical axis direction, and A drive member for moving the movable lens of the finder, and a transmission portion arranged on the periphery of the photographing lens frame for transmitting rotational power by connecting to the drive member. In the finder drive mechanism, even when the transmission section moves in the optical axis direction of the taking lens frame, the connection state with the drive member is maintained and the movable lens of the finder is driven.

A third finder drive mechanism of the present invention is the finder drive mechanism having a finder having a movable lens which moves in the optical axis direction in association with the rotation of a rotary frame provided on the taking lens barrel. A driving member that is connected to a rotating frame and rotates to drive a movable lens of the finder, a moving unit that moves the taking lens barrel including the rotating frame in an optical axis direction, and the taking lens mirror by the moving unit. A supporting means for supporting the driving member rotatably connected to the rotary frame in conjunction with the movement of the frame in the optical axis direction, and supporting the taking lens barrel so as to be slidable in the optical axis direction. There is. In the finder driving mechanism, when the lens barrel is moved in the optical axis direction, the driving member is slidably supported together with the photographing lens barrel while keeping the driving member rotatably connected to the rotating frame. Drives the movable lens of the viewfinder.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a finder drive mechanism and a lens barrel for driving the finder drive mechanism according to a first embodiment of the present invention. FIGS. 2 and 3 show when the lens barrel is extended, respectively.
It is a figure which shows the lens-barrel frame cross section and the finder drive mechanism side surface at the time of being retracted.

The finder drive mechanism is a mechanism for driving the movable lens of the finder forward and backward in association with the rotation of the lens barrel of the taking lens. The lens barrel portion is a movable frame 5 that can be moved along the optical axis O to a retracted position that is a retractable position and a retracted position that can be photographed, and a feed screw 6 as a moving unit that moves the movable frame 5. When the zoom lens of the photographing lens is moved forward and backward together with the moving frame 5,
A taking lens barrel 1 that is driven to rotate during focal length adjustment;
It has a bellows member 4 whose one end is fixed to the moving frame 5.

Further, the finder drive mechanism is a long gear-shaped gear extending in the axial direction, and is supported by the camera body, and the lens frame gear portion 1a fixed to the lens frame 1 is attached to the mirror frame gear portion 1a. A long gear 2 as a drive transmission means in a meshed state within the entire movement range of the frame 1, a cam shaft gear 7a meshing with a part of the long gear 2 and cam shaft cam portions 7b, 7c as end face cam shaped drive members. A cam shaft 7 formed integrally and a driven pin 8 driven by the finder cam
a and 9a, and two viewfinder lenses 8 and 9 which are movable lenses constituting a variable power viewfinder optical system which advances and retreats along a viewfinder optical axis O'parallel to the optical axis O. There is.

The structures of the lens barrel frame and the constituent members of the finder drive mechanism will be described in detail. First, the bellows member 4 has one end fixed to an aperture (not shown) of the camera and the other end 4a fixed to the moving frame 5. The light other than the light incident from the lens supported by the lens barrel 1 is shielded so that it does not enter the film surface, and it is possible to expand and contract by a certain amount in the lens frame moving-out direction and the lens frame moving-in direction.

The feed screw 6 is rotatably supported by a camera body (not shown), and a gear 12 is fixed to one end of the feed screw 6, so that a rotational driving force from a lens frame feeding motor 11 is applied. Transmitted.

The moving frame 5 is movable only with respect to the camera body (not shown) in the feeding direction and the feeding direction of the lens frame 1. A moving frame nut portion 5a is integrally provided on the moving frame 5 and is screwed with the feed screw 6. Therefore, by rotating the feed screw 6 in the CW (clockwise) direction or the CCW (counterclockwise) direction, the moving frame 5 is moved out of the lens barrel 1 (shootable position direction) or in the retracted direction ( It can be moved back and forth).

The lens barrel 1 is fitted in the movable frame 5 so as to be rotatable in the radial direction. Also, through the gear 14 that transmits the driving force from the zoom motor 13, the CW direction or C
It is designed to rotate in the CW direction. Further, a zoom cam (not shown) is integrally provided, and when the lens frame 1 is rotated in the CW direction, the photographing lens is moved in the tele direction, and when rotated in the CCW direction, it is moved in the wide direction. However, it is possible to change the magnification. Further, as described above, the lens frame 1 is fixed to the lens frame 1 which is always engaged with the long gear 2.

The long gear 2 has such a length that it always meshes with the lens frame gear portion 1a even when the lens barrel 1 is moved in parallel along the lens optical axis O in the extending and retracting directions. The cam shaft 7 is an axis parallel to the lens optical axis O,
It is rotatably supported by the camera body. A cam shaft gear portion 7a meshing with the long gear 2 and a finder drive cam having cam shaft cam portions 7b and 7c are integrally arranged in the same rotation center as the cam shaft 7. There is.

A driven pin portion 8a fixed to the first lens 8 and a driven pin portion 9a fixed to the second lens 9 which form a part of the finder optical system are abutted against the cam shaft cam portions 7b and 7c. It is urged by a spring (not shown) so as to urge it. Further, the driven pin portion 8a and the driven pin portion 9a are guided so as to be movable only in the optical axis direction. Also,
The cam shaft cam portions 7b and 7c are cams that change the distance between the driven pin portions 8a and 9a when the cam shaft 7 rotates.

Therefore, when the long gear 2 is rotated, the cam shaft 7 is rotated, and the driven pin portions 8a and 9a slide on the cam shaft cams 7b and 7c, whereby the distance between the first lens 8 and the second lens 9 is increased. To change the magnification of the viewfinder optical system. In addition, when the long gear 2 is rotated in the CW direction, in the wide state, when rotated in the CCW direction,
Change to tele state.

Next, the operation of the finder drive mechanism of this embodiment constructed as described above will be explained. When the feeding motor 11 is rotated in one direction to rotate the feed screw 6 in the lens frame feeding direction, the lens frame 1 and the moving frame 5 are integrally moved in the lens frame feeding direction. At this time, the long gear 2 does not rotate, and the lens frame gear portion 1a is always meshed.
Note that FIG. 2 shows a driving state of the finder driving mechanism in the above-mentioned lens frame extension state.

Then, the lens barrel 1 or the moving frame 5
Is extended to an initial position where it can be photographed and detected by a feeding position sensor (not shown) to stop the movement of the moving frame 5. In this state, when the zoom motor 13 is rotated in a certain direction and the lens barrel 1 is rotated in the CW direction, the taking lens system becomes a tele state. Since the lens frame gear portion 1a and the long gear 2 mesh with each other, the cam shaft 7 rotates, and the cam shaft gear 7a and the cam shaft 7 also rotate in the tele direction. With the rotation of the cam shaft 7, the first lens 8 and the second lens 9 move, and the magnification is changed to the tele side as the finder optical system.

Next, when the zoom motor 13 is rotated in the other direction and the lens barrel 1 is rotated in the CCW direction, it becomes wide, and since the lens frame gear portion 1a and the long gear 2 mesh with each other, the long gear 2 becomes wide. Rotate in the direction. As a result, the first lens 8 and the second lens 9 of the finder optical system move and the magnification is changed to the wide side.

With the lens barrel 1 and the movable frame 5 extended, the feed motor 6 is rotated in the other direction to rotate the feed screw 6 in the lens frame retracting direction, and the lens barrel 1 and the movable frame 5 are rotated. Retract to the retracted position. At this time, the long gear 2 does not rotate and is always in a state of meshing with the lens frame gear portion 1a. FIG. 3 shows the state of the finder drive mechanism when moving in the lens frame retracting direction.

As described above, the finder drive mechanism of the present embodiment adopts a structure in which the lens frame gear portion 1a for advancing and retracting the long gear 2 for transmitting the driving force to the drive mechanism is always meshed. Since it has a small number of parts, it has a simple structure, and it also serves as a drive mechanism for driving the finder optical system that occupies a small space.

Next, the finder drive mechanism of the second embodiment of the present invention will be described. FIG. 4 is a perspective view of the finder drive mechanism and the lens barrel for driving the finder drive mechanism according to the present embodiment. 5 is a sectional view taken along the line AA ′ of FIG. 4, and FIG.
FIG. 6 is a sectional view taken along line BB ′ of FIG. 5. 7 and 8 are views showing a cross section of the lens barrel and a side surface of the finder driving mechanism when the lens barrel is extended and when it is extended, respectively.

The finder drive mechanism of this embodiment is replaced with the long gear 2 applied in the mechanism of the first embodiment.
A drive transmission means (see FIG. 4) composed of a drive shaft 12 as a support means and a drive gear 13 as a drive member slidably fitted in the shaft is applied. In the other drawings, the same components as those of the mechanism of the first embodiment are designated by the same reference numerals in the drawings.

Like the mechanism of the first embodiment, the finder drive mechanism is also a mechanism that is driven in association with the rotation of the lens barrel of the taking lens, but the lens barrel is capable of taking a picture. A movable frame 5 which is movable along the optical axis O to a retracted position which is a retracted position and a retracted position, a feed screw 6 as a moving means for moving the movable frame 5, and a movable frame 5 which moves back and forth. It mainly has a lens barrel frame 11 as a rotary frame that is rotationally driven when the photographing lens undergoes a magnification change operation, and a bellows member 4 whose one end is fixed to a movable frame 5.

The finder drive mechanism is slidably fitted into a drive shaft 12 which is rotatably supported by the camera body, and moves in the axial direction together with the lens frame 11 to move the movable lens frame 1.
The above-mentioned drive gear 13 that maintains a meshed state in the entire movement range of the lens frame 11 with respect to the lens frame gear portion 11c fixed to the No. 1 gear, the gear 14 fixed to the drive shaft 12, and the gear 14. A cam shaft 7 integrally formed with a cam shaft gear 7a and cam shaft cam portions 7b and 7c as end cam-shaped driving members, and a driven pin 8a driven by the finder cam.
It mainly has two finder lenses 8 and 9 which are movable lenses which have a zooming finder optical system 9a which advances and retreats along a finder optical axis O'parallel to the optical axis O.

The structures of the lens barrel frame portion and the components of the finder drive mechanism will be described in detail. The bellows member 4, the feed screw 6, and the moving frame 5 constituting the lens barrel portion.
Further, in the finder drive mechanism, a cam shaft 7 that integrally has a finder drive cam, a gear 7a, and the like,
The first lenses 8 and 9 having the driven pins 8a and 9a are also the first lenses.
The structure is the same as that applied to the mechanism of the embodiment, and detailed description thereof will be omitted.

The lens barrel 11 is fitted in the movable frame so as to be rotatable in the radial direction. Further, similarly to the mechanism of the first embodiment, the zoom motor 13 is operated in the CW direction or C
It is designed to rotate in the CW direction. When the lens frame 11 is rotated in the CW direction by the zoom motor 13, the photographing lens is moved in the tele direction, and when rotated in the CCW direction, it is moved in the wide direction to change the magnification.

Further, the drive gear 1 is attached to the lens barrel 11.
The lens frame gear portion 11c which is always meshed with the lens 3 is fixed.
Further, gear pushing members 11b and 11a that are pressed against the side surface of the drive gear 13 to drive in the same direction when the lens frame moves in the feeding direction or the feeding direction are integrally provided (FIG. 7). , 8).

The drive gear 13 is adapted to mesh with the lens frame gear portion 11c of the lens frame 11 and has a D-shaped fitting hole 13a. The drive gear 13 has a fitting hole 1
D-cut surface 12 that can be fitted in 3a and has the same center of rotation
The rotational force of the drive gear 13 is transmitted to the drive shaft 12 while being fitted in the drive shaft 12 having a and sliding in the thrust direction.

Next, the operation of the finder drive mechanism of this embodiment constructed as described above will be explained. When the feeding motor 11 is rotated in one direction to rotate the feed screw 6 in the lens frame feeding direction, the lens frame 11 and the moving frame 5 are integrally moved in the lens frame feeding direction. At this time, the drive gear 13
Does not rotate, but moves in the feeding direction with the lens frame gear portion 11c engaged. FIG. 7 shows the drive state of the finder drive mechanism in the above-mentioned lens frame extension state.

Then, it is detected by a feeding position sensor (not shown) that the lens barrel 11 or the moving frame 5 has been extended to an initial position where photographing is possible, and the movement of the moving frame 5 is stopped. In this state, if the zoom motor 13 is rotated in a certain direction and the lens barrel 11 is rotated in the CW direction, the taking lens system will be in the tele state. Further, since the lens frame gear portion 11c and the drive gear 13 mesh with each other, the cam shaft 7
Rotates, and the cam shaft gear 7a and the cam shaft 7 also rotate in the tele direction. With the rotation of the cam shaft 7, the first lens 8 and the second lens 8
The lens 9 moves, and the viewfinder optical system is zoomed to the tele side.

Next, when the zoom motor 13 is rotated in the other direction and the lens barrel 11 is rotated in the CCW direction, it becomes wide, and the lens frame gear portion 11c and the drive gear 13 mesh with each other. Rotates in the wide direction. As a result, the first lens 8 and the second lens 9 of the finder optical system move and the magnification is changed to the wide side.

When the lens barrel 11 and the movable frame 5 are extended, the feed motor 11 is rotated in the other direction, and the feed screw 6 is rotated in the feed direction of the lens frame.
The lens barrel 11 and the moving frame 5 move integrally in the retracting direction to the retracted position. At this time, the drive gear 13 does not rotate and moves on the drive shaft 12 while meshing with the lens frame gear portion 11c. FIG. 8 shows the state of the finder drive mechanism when moving in the lens frame retraction direction.

As described above, according to the finder drive mechanism of this embodiment, it is not necessary to use a long gear,
Since the D-cut drive shaft 12 and the drive gear 13 are used instead, not only is it cost-effective, but the space required for the drive gear 13 alone can be minimized, and the drive In the case of a lens frame and a moving frame that move integrally with the gear 13, the space can be effectively used, so that the camera body can be downsized and the cost can be reduced.

(Appendix) According to the embodiment described above,
The finder drive mechanism described below can be proposed. That is, (1) a finder having a taking lens barrel that can move in the optical axis direction and rotate about the optical axis, and a movable lens that moves in the optical axis direction in conjunction with the turning of the taking lens barrel. And a drive member for moving the movable lens of the finder, and a transmission unit arranged on the periphery of the photographing lens lens frame and connected to the drive member for transmitting rotational force. The finder drive mechanism, wherein the transmission unit maintains the connection state with the drive member even when the taking lens barrel moves in the optical axis direction.

(2) A photographic lens barrel movable along the optical axis, a finder lens having at least one movable lens, a drive member for driving the movable lens of the finder lens, and a drive from a drive source. A transmission member that couples a force to the drive member to transmit rotational force, and the transmission member moves in the optical axis direction in accordance with the movement of the photographing lens barrel in the optical axis direction, and A finder drive mechanism, characterized in that the drive force of a source is transmitted to the drive member.

(3) In the supplementary note (2), the taking lens barrel is a variable focal length lens barrel, and the finder lens is a variable magnification finder which changes its magnification in conjunction with the taking lens barrel. Finder drive mechanism characterized by.

(4) In the viewfinder drive mechanism according to the supplementary note (2), the drive member has a length equal to or greater than a moving range of the transmission member in the optical axis direction.

(5) A finder drive mechanism as set forth in appendix (2), wherein the drive member and the transmission member have gears.

(6) In appendix (2), the drive member moves along the optical axis of the transmission member in the optical axis direction, and the moving gear slides along the optical axis. A finder drive mechanism comprising: a shaft which is rotatably supported and integrally rotatably supported so as to transmit the rotation from the moving gear.

(7) Depending on the photographing lens mirror frame which can be moved back and forth between the extended position and the retracted position and which can be rotated at the extended position to switch the focal length, and the focal length of the photographing lens mirror frame. And a zooming finder having a zooming movable lens that moves in the optical axis direction, and a drive that can transmit the rotation of the shooting lens to the movable lens of the viewfinder regardless of the movement of the shooting lens barrel to move back and forth. A finder drive mechanism comprising: a transmission means.

(8) In a viewfinder drive mechanism having a viewfinder having a movable lens that moves in the optical axis direction in conjunction with the rotation of a rotary frame provided with a taking lens barrel, the rotary frame is connected to the rotary frame. Gears, driving means for integrally rotating with the gears to drive the movable lens of the finder, moving means for moving the taking lens barrel including the rotating frame in the optical axis direction, and the moving means. In conjunction with the movement of the taking lens barrel in the optical axis direction, the gear is
A finder drive mechanism, comprising: a supporting unit that supports the rotating frame while being rotatably connected to the taking lens barrel so as to be slidable in the optical axis direction.

(9) A photographic lens frame which can be moved back and forth in the optical axis direction between the extended position and the extended position, and which rotates the rotary frame at the extended position to switch the focal length, and the above photographic lens mirror. A variable magnification finder that has a variable magnification movable lens that moves in the optical axis direction according to the focal length of the frame, a gear that is connected to the rotating frame and rotates, and the finder that moves integrally with the gear to move the finder. A driving means for driving the lens and a supporting means for supporting the gear so as to be rotatable with the rotating frame and supporting the taking lens barrel so as to be slidable in the optical axis direction, and the gear in the advancing and retracting direction. It is provided on the photographing lens lens frame so as to be sandwiched between the photographing lens lens frame and the optical axis of the photographing lens lens frame together with the photographing lens lens frame when the photographing lens lens frame is advanced or retracted to the retracted position or the retracted position. Slide in the direction Finder driving mechanism, characterized by comprising a convex portion.

[0045]

As described above, in the finder drive mechanism of the present invention, even when the lens barrel is extended from the retracted position to the photographing position, the driving force from the motor is transmitted through the drive transmission means.
The forward / backward drive force can be transmitted to the movable lens of the viewfinder, and the size and cost of the camera can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view of a finder drive mechanism and a lens barrel that drives the finder drive mechanism according to a first embodiment of the present invention.

FIG. 2 is a view showing a cross section or a side surface of a lens barrel and a finder driving mechanism when the lens barrel of FIG. 1 is extended.

3 is a view showing a cross section or a side surface of the lens barrel and the finder driving mechanism when the lens barrel of FIG. 1 is retracted.

FIG. 4 is a perspective view of a finder drive mechanism and a lens barrel for driving the finder drive mechanism according to a second embodiment of the present invention.

5 is a cross-sectional view taken along the line AA ′ of FIG.

6 is a sectional view taken along line BB ′ of FIG.

7 is a view showing a cross section or a side surface of the lens barrel and the finder driving mechanism when the lens barrel of FIG. 4 is extended.

8 is a view showing a cross section or a side surface of the lens barrel and the finder driving mechanism when the lens barrel of FIG. 4 is retracted.

[Explanation of symbols]

 1, 11 ... Photographic lens mirror frame, rotary frame 2 ... Long gear (drive transmission means, transmission portion) 6 ... Feed screw (moving means) 7 ... Cam shaft (driving member) 8, 9 ... Movable Lens 12 ... Drive shaft (drive transmission means, support means) 13 ... Drive gear (drive transmission means, transmission portion)

Claims (3)

[Claims] 1. A photographing lens lens frame which can be moved back and forth between a feeding position and a feeding position and which is rotatable around an optical axis, a finder having a movable lens which moves in the optical axis direction, and the photographing lens lens frame. The drive mechanism for transmitting the rotation of the photographing lens to the movable lens of the finder regardless of the forward / backward movement of the finder, and a finder drive mechanism. 2. A photographic lens frame capable of moving in the optical axis direction and rotating about the optical axis, a finder having a movable lens moving in the optical axis direction, and a driving member for moving the movable lens of the finder. And a transmission portion which is arranged on the periphery of the photographing lens lens frame and which is coupled to the drive member and transmits rotational force. The transmission portion includes the photographing lens lens frame in the optical axis direction. A finder drive mechanism characterized in that the finder drive mechanism is maintained in a connected state with the drive member even when the finder drive mechanism is moved. 3. A finder drive mechanism having a finder having a movable lens that moves in the optical axis direction in association with the rotation of a rotary frame provided on a taking lens barrel, the rotary mechanism being connected to the rotary frame and rotating. A drive member for driving the movable lens of the finder, a moving means for moving the taking lens barrel including the rotating frame in the optical axis direction, and an interlocking movement of the taking lens barrel by the moving means in the optical axis direction. And a supporting means for supporting the drive member so as to be rotatable in the optical axis direction together with the photographing lens lens frame while rotatably connected to the rotary frame. .